presentation about boiler, boiler accesories, mounting and types

1. TECHNIQUE POLYTECHNIC
INSTITUTE
MECHANICAL ENGINEERING DEPARTMENT
PPT PRESENTATION ABOUT ‘BOILER’
VENUE – TPI SEMINAR HALL
<< PRESENTED BY >>
<< group 12 >>
Bibek Kundu, Sumit Golder, Pradyut Bera, Tanay Bera, Sagar Chaki

2. BOILER
What is a boiler ?
 A boiler is a closed vessel, which used to generate steam from water
and whose minimum capacity Should be more than 22.75 liter.
What is the Function of a boiler ?
 The function of the boiler is to transfer heat to the water in the efficient
Manner
General working principle of a boiler
 The chemical energy is converted to heat energy by the combustion process
and the produced heat is absorb by the boiler.
TECHNIQUE POLYTECHNIC INSTITUTE/DME 6th

3. DIFFERENT PARTS OF A BOILER
Shell
Chimney
It is upper portion of boiler which consist of a hollow cylinder body
made up high quality steel plate riveted Together.
It is a lower and vital part of boiler on which the fuel is burnt. It consist of
several CI bar fitted parallel, Certain gap is provide in between to adjacent bar
to flow air and also give a passage for ashes to drop on ash pits.
Grate & Furnace
Chimney is that part through which the burnt gas is discharge to atmosphere
TECHNIQUE POLYTECHNIC INSTITUTE/DME 6th

4. BASIC DIAGRAM OF A BOILER
Water tube
Boiler shell
TECHNIQUE POLYTECHNIC INSTITUTE/DME 6th

5. CLASSIFICATION OF BOILER
Purpose of use
Relative position of water and flue gas
Axis position of boiler cell
Nature of use furnace position
Nature of fuel use
Nature of circulation
Locomotive, marine, textile industry,
Power station
Fire tube boiler (example – Cochran boiler)
Water tube boiler ( Babcock Wilcocx boiler)
Virtical boiler, horizontal boiler
Internally fired, externally fired
Oil fuel (volex boiler), solid or gaseous fuel
(babcock wilcocx)
Free circulation, force circulation (example
– lamont boiler is force circulation
Cochran,lancashare is free circulation)
TECHNIQUE POLYTECHNIC INSTITUTE/DME 6th

6. FIRE TUBE BOILER (Cochran boiler)
TECHNIQUE POLYTECHNIC INSTITUTE/DME 6th

7. Coal is fed into the grate through the fire
hole and burnt. Ash formed during
burning is collected in the ash pit
provided just below the grate and then it
is removed manually.
The host gases from the grate pass
through the flue pipe to the combustion
chamber. The hot gases from the
combustion chamber flow through the
horizontal fire tubes and transfer the heat
to the water by convection.
The flue gases coming out of fire tubes
pass through the smoke box and are
exhausted to the atmosphere through the
chimney.
Smoke box is provided with a door for
cleaning the fire tubes and smoke box.
Working principle of Cochran boiler
TECHNIQUE POLYTECHNIC INSTITUTE/DME 6th

8. Water tube Babcock Wilcox boiler
boiler
shell
Water tube
Fire brick
liner
Fuel feed
system
Combustion
chamber
base
chimney
TECHNIQUE POLYTECHNIC INSTITUTE/DME 6th

9. Working principle of Babcock Wilcox boiler
The hot flue gases rise upward and pass across the left-side
portion of the water tubes. The baffles deflect the flue gases
and hence the flue gases travel in the zig-zag manner (i.e., the
hot gases are deflected by the baffles to move in the upward
direction, then downward and again in the upward direction)
over the water tubes and along the superheater. The flue gases
finally escape to atmosphere through chimney.
That portion of water tubes which is just above the furnace is
heated comparatively at a higher temperature than the rest of
it. Water, its density being decreased, rises into the drum
through the uptake-header. Here the steam and water are
separated in the drum. Steam being lighter is collected in the
upper part of the drum. The water from the drum comes down
through the down –comer into the water tubes.
A continuous circulation of water from the drum to the water
tubes and water tubes to the drum is thus maintained. The
circulation of water is maintained by convective currents and
is known as “natural circulation”.
A damper is fitted as shown to regulate the flue gas outlet and
hence the draught.
The boiler is fitted with necessary mountings. Pressure gauge
and water level indicator are mounted on the boiler at its left
end. Steam safety valve and stop valve are mounted on the top
of the drum. Blow-off cock is provided for the periodical
removed of mud and sediments collected in the mud box.
TECHNIQUE POLYTECHNIC INSTITUTE/DME 6th

10. Advantage of water tube over fire tube
TECHNIQUE POLYTECHNIC INSTITUTE/DME 6th

11. High pressure boilers
Now a days due to heavy demand of electricity, maximum power plant using modern
High pressure boiler. Which are capable for generating steam at a pressure of 250 bar
And temperature 550℃ which is super heated .
Cause behind using high pressure boiler
Fuel consumption
very low
High thermal
efficiency
Increasing plant
efficiency
Example of high pressure boiler
La mont boiler Loeffler boiler Volex boiler Benson boiler
TECHNIQUE POLYTECHNIC INSTITUTE/DME 6th

12. Boiler Accessories
 What is boiler accessories ?
Boiler accessories are those appliances and plants which are
used along with the boiler to improve the operating condition and
Overall efficiency of a boiler
The useful accessories are
A
B
C
D
Economizer
Super heater
injectors
Feed pump
TECHNIQUE POLYTECHNIC INSTITUTE/DME 6th

13. Economizer
Used to preheat the feed water with
help of waste hot flue gas
> Placed in to chimney
Increase the steam quality, making
steam super heated
> Placed in furnace
Super heater
TECHNIQUE POLYTECHNIC INSTITUTE/DME 6th

14. Used to feed condenser water again to
boiler and recirculate
> Placed in condenser outlet
Rotary feed pump
Boiler injector
Used to inject feed water in to the
boiler
> Placed in boiler shell
TECHNIQUE POLYTECHNIC INSTITUTE/DME 6th

15. TECHNIQUE POLYTECHNIC INSTITUTE/DME 6th
Boiler Mounting
 What is boiler mounting ?
Boiler mounting is those mechanical appliance which are considered essencial
for operating a boiler smoothly and safely
The following important mountings are
1
4
3
2
5
6
Water level indicator
Pressure gauge
Safety valve
Fusible plug
Steam stop valve
Blow off valve

16. TECHNIQUE POLYTECHNIC INSTITUTE/DME 6th
Used to indicate water level in boiler
shell
> Placed on boiler shell verticallyWater level indicator
Pressure guage
Used to indicate steam pressure in shell
> Placed on boiler shell vertically

17. TECHNIQUE POLYTECHNIC INSTITUTE/DME 6th
Used to discharge excess steam thrugh
it
> Placed on boiler shell
Spring loaded
safety valves
Fusable plug
Used to discharge water from boiler
put off furnace
> Placed bellow boiler shell

18. TECHNIQUE POLYTECHNIC INSTITUTE/DME 6th
Steam stop valve
Used to collect steam from boiler
> Placed top of the boiler shell
Blow off valve
Used to remove sediments of boiler
> Placed side bottom of boiler

19. TECHNIQUE POLYTECHNIC INSTITUTE/DME 6th
Boiler Drought
 What is drought of boiler ?
Drought is the difference of pressure which causes a flow of air to take place from
out side atmosphere into the boiler furnace for complete combustion of fuel
Drought
classification
natural
artificial
fan
drought
Steam
jet
drought
forced
Induced
Induced
forced

20. TECHNIQUE POLYTECHNIC INSTITUTE/DME 6th
Thank you
Prepared by Bibek Kundu
DME 12
6th semester